1. Field of the Invention
The present invention relates to a multijointed bending mechanism in which a plurality of bending pieces can be independently manipulated by manipulation wires, and to a multijointed medical equipment having such multijointed bending mechanism.
2. Description of the Related Art
In general, an insertion portion of a piece of medical equipment such as an endoscope is provided with a bending portion. Bending pieces are rotatably coupled with each other in the bending portion. A manipulation wire is connected only to a bending piece at the most extreme end of the bending portion. The bending portion is bent in its entirety by pushing and pulling the manipulation wire. More specifically, since the respective bending pieces cannot be independently rotated, it is difficult for the bending pieces to take a predetermined bending state.
To cope with the above problem, in Patent Document 1, repellent force application means is disposed in the base end portion of a bending portion. When the bending portion is bent by a manipulation wire, the repellent force application means begins to bend the bending portion preferentially from the extreme end portion thereof. Further, in Patent Document 2, balloons are interposed between bending pieces, respectively. Rotation intervals between bending pieces are adjusted by the expansion and contraction of the balloons. With this configuration, when a bending portion is bent, the radius of bending of the bending portion can be variably adjusted.
Patent Document 1: Jpn. Pat. Appln. KOKAI Publication No. 2003-126024
Patent Document 2: Jpn. Pat. Appln. KOKAI Publication No. 06-105797